What constitutional principle is illustrated by the ability of Congress to create laws, which can then be vetoed by the president or overturned by the Supreme Court?

The principle illustrated by Congress's ability to create laws, which can be vetoed by the president or overturned by the Supreme Court, is checks and balances. This principle is fundamental to the structure of the U.S. government as it ensures that no single branch becomes too powerful. Each branch—legislative, executive, and judicial—has specific powers that can limit or check the actions of the others.

For example, while Congress has the power to make laws, the president has the authority to veto those laws, thereby providing a check on legislative power. Additionally, the judicial branch, through its role in interpreting laws, can declare laws unconstitutional, serving as a check on both Congress and the president. This interaction between the branches fosters accountability and ensures that a balance of power is maintained within the government.

The other options refer to different concepts. Separation of powers speaks to the distinct functions and responsibilities assigned to each branch. Judicial review refers specifically to the power of the courts to evaluate legislation and executive actions. Popular sovereignty pertains to the concept that the authority of the government is derived from the consent of the governed, emphasizing the role of the people in a democratic system.